Word.ws English Dictionary

aptychus

aptychus noun: a hard calcareous plate forming part of the body of an ammonite.

Noun

aptychus (plural aptychi)

  1. A hard calcareous plate forming part of the body of an ammonite.
    • It wasn't until the 1970s that paleontologists had amassed enough evidence to be certain that aptychi were modified lower jaws.2017, Danna Staaf, Squid Empire, ForeEdge, →ISBN, page 95

Forms of aptychus

pluralaptychi

Origin of aptychus

Modern Latin, from a- + Ancient Greek πτυχή (ptukhḗ, “fold, layer”).

Questions about aptychus

What does aptychus mean?
Aptychus means a hard calcareous plate forming part of the body of an ammonite.
What part of speech is aptychus?
Aptychus is a noun.
What is the plural of aptychus?
The plural of aptychus is aptychi.

Words near aptychus in the dictionary

  1. APTU
  2. APTUs
  3. aptyalia
  4. aptyalism
  5. aptychi
  6. aptychus
  7. APU
  8. apu mallku
  9. apu mallkus
  10. apuanite
  11. apud

Source and license

Adapted from Wiktionary: aptychus (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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